Elements of Music

34 35 thE thrEE MInors natural, harmonic, and melodic The active role of leading tones in harmonic music creates complexities for minor keys. The natural dominant chord in minor is not a major chord, and the need for a leading tone necessitates altering it, and the scale from which it is built. In the case of natural minor, we are in the presence of the Aeolian mode, which occurs naturally as the relative to any major scale, started a third lower. Raising the third in the dominant chord, the seventh of the scale, creates harmonic minor, altered for harmonic purposes. The scale that results from this, however, contains an audible gap between the flatted minor 6th and the natural major 7th, an augmented second, which does not always work melodically, sounding like an interval from nonWestern music. To smooth out this melodic gap, the 6th scale degree is also altered, raised, so that the ascent in minor resembles a major scale in its upper four notes. This is melodic minor, which is sometimes said to have two forms ascending and descending, raising and lowering the 6th and 7th accordingly. In fact, descending melodic minor is identical to natural minor. Triads of the three minors are shown below. Opposite page These three minor scales are used interchangeably depending upon the composers needs, and adhere to basic rules about the use of chromaticism in the minor mode. These scales, like majorIonian, can be used as starting points to generate others, so in fact there are seven modes of harmonic minor and seven modes of melodic minor shown below. Left Natural minor is identical to a major scale a minor third above. So A minor and C major are in fact the same notes, shifted a third apart. Natural minor, being Aeolian, already shares the same pitches as its relative major, Ionian, therefore they share the same key signature see page 11. W H W W H A H W H W W W W H H W W W W H W W W W W H W H W W W H W H W W W H W H W W W H W H W W W H W H W W W W H W W H A H W W W H A H W H W H A H W H W H A H W H W W A H W H W W H H W H W W H A